Magnetic field generator and magnetocaloric device comprising said magnetic field generator

Abstract

A magnetic field generator ( 10 ) comprising an assembly ( 20 ) of permanent magnets ( 30 ) inside which the magnetic flux concentrates. The assembly comprises opposed first and second elements ( 21, 22 ) that include magnets ( 30 ). The elements ( 21 ) and ( 22 ) are arranged substantially in the same plane and surrounded by respective closing mechanisms ( 51, 52 ). The permanent magnets ( 30 ) are made up of parallelepipedal blocks, arranged substantially in an arc of a circle according to three areas: a central area ( 60 ), a first side area ( 70 ) on one side of the central area ( 60 ), and a second side area ( 80 ) on the other side of the central area ( 60 ). The permanent magnets ( 30 ) of the first and second ( 70, 80 ) side areas have opposite directions of magnetization. Two parts ( 91 ) and ( 92 ) of a ferromagnetic material, forming a magnetic flux concentrator ( 90 ), are arranged on either side of the air gap ( 40 ).

1 - 12 . (canceled) 
     
     
         13 . A magnetic field generator ( 10 ;  100 ;  110 ;  120 ) comprising:
 at least one assembly ( 20 ) of permanent anisotropic magnets ( 30 ;  31 ) for creating a magnetic flux and defining an air gap ( 40 ) inside which the magnetic flux is concentrated, the assembly ( 20 ) of magnets comprising:
 a first element ( 21 ) and a second element ( 22 ) mounted across from each other symmetrically relative to an axis (AA) perpendicular to the transverse axis (B-B) of the air gap ( 40 ), 
 each of the first ( 21 ) and second ( 22 ) elements comprising at least three permanent magnets ( 30 ;  31 ); and 
 the first ( 21 ) and the second ( 22 ) element of the assembly ( 20 ) of magnets being disposed generally in a same plane and at least partially surrounded by mechanisms for closing the magnetic field ( 51 ,  52 ), respectively, 
   wherein the permanent magnets ( 30 ;  31 ) in the first ( 21 ) and second ( 22 ) elements of the assembly ( 20 ) of magnets comprise blocks that are parallelepipedal in shape,   the permanent magnets ( 30 ;  31 ) are arranged generally in a circular arc in central and first and second lateral zones, with the central zone ( 60 ) located facing the air gap ( 40 ), the first lateral zone ( 70 ) located on one side of the central zone ( 60 ) and the second lateral zone ( 80 ) located on the other side of the central zone ( 60 ),   the permanent magnets ( 30 ;  31 ) of the first ( 70 ) and second ( 80 ) lateral zones are magnetized in the opposite direction from an axis (A-A) which extends perpendicular to a transverse axis (B-B) of the air gap ( 40 ), and   at least two pieces of ferromagnetic material ( 91 ) and ( 92 ), which comprise a magnetic flux concentrator ( 90 ), are located on either side of the air gap ( 40 ), respectively, between the permanent magnets ( 30 ;  31 ) in the first lateral zones ( 70 ) of the first ( 21 ) and second ( 22 ) element of the assembly ( 20 ) of magnets, located on one side of the central zones ( 60 ) and between the permanent magnets ( 30 ) in the second lateral zones ( 80 ) of the first ( 21 ) and second ( 22 ) element of the assembly ( 20 ) of magnets, located on the other side of the central zones ( 60 ).   
     
     
         14 . The magnetic field generator according to  claim 13 , wherein the permanent magnets ( 30 ,  31 ) comprising parallelepipedal blocks have one of a rectangular transverse cross-section ( 30 ) and a trapezoidal transverse cross-section ( 31 ). 
     
     
         15 . The magnetic field generator according to  claim 13 , wherein the magnetic field generator comprises several groups of assemblies ( 20 ) of permanent anisotropic magnets ( 30 ;  31 ), the assemblies are identical, and the group comprises a single air gap ( 40 ), each group of magnet assemblies creates a magnetic flux and comprises a means for concentrating the magnetic flux generated by the group of assemblies ( 20 ) of magnets inside the single air gap ( 40 ). 
     
     
         16 . The magnetic field generator ( 100 ) according to  claim 13 , wherein the magnetic field generator comprises several groups of assemblies ( 20 ) of permanent anisotropic magnets, the assemblies of magnets are different, juxtaposed, and designed to form a single air gap ( 40 ), each group of magnet assemblies is designed to create a magnetic flux and comprises a means for concentrating the magnetic flux generated by the groups of assemblies ( 20 ) of magnets inside the single air gap ( 40 ). 
     
     
         17 . The magnetic field generator according to  claim 13 , wherein each of the mechanisms ( 51 ,  52 ) for closing the magnetic field of the first ( 21 ) and second ( 22 ) elements of the assembly ( 20 ) of magnets has a generally arc-shaped interior profile that corresponds to a circular arc arrangement of the central, the first lateral and the second lateral zones ( 60 ,  70 ,  80 ) of permanent magnets ( 30 ) of the first ( 21 ) and second ( 22 ) elements of the assembly ( 20 ) of magnets. 
     
     
         18 . The magnetic field generator according to  claim 17 , wherein the permanent magnets ( 30 ;  31 ) are designed, in the assembly ( 20 ) of magnets, so that
 in the central zone ( 60 ) their magnetization is approximately tangential to the adjacent surface of the mechanism ( 51 ,  52 ) for closing the corresponding magnetic field, and   in the first and second lateral zones ( 70 ,  80 ) their magnetization is perpendicular to the corresponding surface of the mechanism ( 51 ,  52 ) for closing the corresponding magnetic field.   
     
     
         19 . The magnetic field generator according to  claim 17 , wherein in the first and the second lateral zones ( 70 ,  80 ) magnetization of the permanent magnets ( 30 ;  31 ) is perpendicular to the adjacent surface of the two pieces ( 91 ,  92 ) of the corresponding magnetic flux concentrator ( 90 ). 
     
     
         20 . The magnetic field generator according to  claim 17 , wherein the permanent magnets ( 30 ) in the first and the second lateral zones ( 70 ,  80 ) are each mounted on one of the pieces ( 91 ,  92 ) of the corresponding magnetic flux concentrator ( 90 ). 
     
     
         21 . The magnetic field generator according to  claim 20 , wherein the pieces ( 91 ,  92 ) of the magnetic flux concentrator ( 90 ) have oblique surfaces on one side corresponding in shape to the surface of the corresponding permanent magnets ( 30 ;  31 ) in the two lateral zones ( 70 ,  80 ) and a projecting portion ( 55 ) on the other side at the level of the air gap ( 40 ). 
     
     
         22 . The magnetic field generator according to  claim 13 , wherein each first ( 21 ) element and each second ( 22 ) element of the assembly ( 20 ) of magnets is respectively associated with a first mechanism ( 51 ) and a second ( 52 ) mechanism for closing the magnetic field. 
     
     
         23 . The magnetic field generator according to  claim 13 , wherein each first ( 21 ) element and each second ( 22 ) element of the assembly ( 20 ) of magnets is respectively associated with several first mechanisms ( 51 ) and second mechanisms ( 52 ) for closing the magnetic field. 
     
     
         24 . A thermal magnetocaloric device comprising at least one magnetic field generator ( 10 ;  100 ;  110 ;  120 ) comprising at least one assembly ( 20 ) of permanent anisotropic magnets ( 30 ;  31 ) for creating a magnetic flux and defining an air gap ( 40 ) inside which the magnetic flux is concentrated, the assembly ( 20 ) of magnets comprising a first element ( 21 ) and a second element ( 22 ) mounted across from each other symmetrically relative to an axis (AA) perpendicular to the transverse axis (B-B) of the air gap ( 40 ), each of the first ( 21 ) and second ( 22 ) elements comprising at least three permanent magnets ( 30 ;  31 ); and the first ( 21 ) and the second ( 22 ) element of the assembly ( 20 ) of magnets being disposed generally in a same plane and at least partially surrounded by mechanisms for closing the magnetic field ( 51 ,  52 ), respectively, the permanent magnets ( 30 ;  31 ) in the first ( 21 ) and second ( 22 ) elements of the assembly ( 20 ) of magnets comprise blocks that are parallelepipedal in shape, the permanent magnets ( 30 ;  31 ) are arranged generally in a circular arc in central and first and second lateral zones, with the central zone ( 60 ) located facing the air gap ( 40 ), the first lateral zone ( 70 ) located on one side of the central zone ( 60 ) and the second lateral zone ( 80 ) located on the other side of the central zone ( 60 ), the permanent magnets ( 30 ;  31 ) of the first ( 70 ) and second ( 80 ) lateral zones are magnetized in the opposite direction from an axis (A-A) which extends perpendicular to a transverse axis (B-B) of the air gap ( 40 ), and at least two pieces of ferromagnetic material ( 91 ) and ( 92 ), which comprise a magnetic flux concentrator ( 90 ), are located on either side of the air gap ( 40 ), respectively, between the permanent magnets ( 30 ;  31 ) in the first lateral zones ( 70 ) of the first ( 21 ) and second ( 22 ) element of the assembly ( 20 ) of magnets, located on one side of the central zones ( 60 ) and between the permanent magnets ( 30 ) in the second lateral zones ( 80 ) of the first ( 21 ) and second ( 22 ) element of the assembly ( 20 ) of magnets, located on the other side of the central zones ( 60 ); and
 one magnetocaloric element traversed by a heat-transporting fluid circulating alternately towards a first extremity of the thermal generator and towards a second extremity, as well as a means for magnetically activating and deactivating the displacement of the magnetocaloric element relative to the magnetic field generator;   wherein the magnetic field generator is designed to constitute the means for magnetically activating and deactivating the magnetic element, and in that the magnetocaloric element is located in the air gap ( 40 ) of the magnetic field generator ( 10 ;  100 ;  110 ;  120 ).